A good way to ensure that one reactant fully reacts is to use an excess of the other reactant. The other reactant becomes a limiting factor and controls how much of each product is produced. … While using excess reactants can help to increase percentage yields, this is at the expense of atom economy.

Which is more important the limiting reactant or the excess reactant?

Find the limiting reagent by calculating and comparing the amount of product each reactant will produce. Balance the chemical equation for the chemical reaction. … The reactant that produces a lesser amount of product is the limiting reagent. The reactant that produces a larger amount of product is the excess reagent.

How do excess reagent affects the chemical reaction?

In a chemical reaction, reactants that are not used up when the reaction is finished are called excess reagents. The reagent that is completely used up or reacted is called the limiting reagent, because its quantity limits the amount of products formed. It represents a reaction of a metal and a diatomic gas chlorine.